Models and simulation for analysis of a computer network

Computer communication networks are becoming common items in office and manufacturing environments. Electrical component characteristics and network operation are understood by a small number of engineers and designers with knowledge about communication networks. This lack of widespread knowledge was recognized when a high-speed computer communication network was being installed in the integrated circuit (IC) fabrication facility in the Solid-State Electronics Laboratory (SSEL) at The University of Michigan. At a reasonable cost, it was not possible to independently verify a proper design for that facility. To develop a capability to analyze computer communication networks, two important methods were developed: (1) a model parameter extraction algorithm for network components and (2) a simulation algorithm to analyze electrical operation of an overall network. The model parameter extraction algorithm is crucial to the success of this effort. The model parameter extraction algorithm is based on a consistent mathematical formulation of multi-port models to represent the real-world situation of components with several input/output ports, and components that have specifications cited in terms of attenuation losses. The extraction algorithm has been used to compute model parameters for components having 1 port to 10 ports. The extracted model parameters are then placed in the network analysis simulation algorithm to compute characteristics for the complete network. The simulator includes automated input of the computer network description with component specifications, internal models of computer network components, automatic equation generation, equation solution methods, and output (display) of electrical operational characteristics of the computer network. The simulator has been used to analyze the network characteristics of the SSEL IC facility and other networks, including a generic computer network that was developed to exercise and validate all formulated models in the simulator. The important results of this article are: (1) a simulation algorithm to analyze computer communication networks using internal models of components, (2) an algorithm for model parameter extraction for the components of the networks, and (3) analysis of sample computer networks to validate the models, the model parameter extraction algorithms, and the simulation algorithm